The CSS scheme included on most Hollywood-produced DVDs requires a software key inside DVD players to view the underlying movie. Hollywood says 321 Studios violated the law by distributing that key in its software, sold under such names as DVD Copy Plus and DVD X Copy.

A lawyer for the company argued otherwise.

``What a DVD player does and what our product does are exactly the same thing,'' Daralyn Durie told U.S. District Judge Susan Illston. ``The question here is not whether we have the authority. It's whether the users have the authority to access the content.''

The company has sold about a half-million copies of software titles that allow the user to make backup copies of DVD movies to blank DVDs or CDs.

The software company says its products merely give consumers fair use of the movies they've purchased - backing up expensive copies of children's movies in case the originals get scratched or copying snippets of films for educational and journalistic use.

But the traditional fair-use doctrine in this case has given way to making DVDs fair game for movie piracy, Hollywood lawyers contend.

``Clearly, 321 does not think of fair use,'' attorney Russell Frackman argued on behalf of the studios. ``What 321 sells is a commercial circumvention product.''

Frackman is a veteran of such copyright issues, having led the music industry to a courtroom victory over Napster, the song-swapping company that folded under legal pressure.

While Frackman insisted 321 Studios' practices were illegal, he sought to deflect any notion that Hollywood was calling consumers movie thieves.

``It's not a copyright case. It's not a case against the user,'' Frackman told the court. ``It is precisely the type of case Congress foresaw, predicted and legislated.''

A federal appeals court in New York already ruled for Hollywood in an earlier case, forcing Web site operator Eric Corley to remove links to a DVD decryption program.

Although Illston said she was persuaded by that ruling, she grilled Hollywood's lawyers on the time limitations of copyright materials and how those rights may be effectively extended because of the anti-piracy protections.

If the copyright for a movie lapses, she asked, doesn't it live on indefinitely by continually preventing the owner of a DVD from accessing the movie as he or she sees fit?

Mark Radcliffe, an attorney on intellectual property who is not involved in the case, said the entertainment industry may be pushing too hard to protect its content.

``Copyright is only supposed to grant enough rights to make works available to the public,'' he said. ``They've taken a much more absolutist position that copyright is some sort of birthright.''

He added that the case may hinge on how people are actually using 321 Studio's software - whether the company can prove that scratched or worn DVDs are truly a problem for consumers.